Magnum Lift Systems, model SPEL single leg electric over hydraulic gooseneck trailer Jack with electric override in case of loss of trailer power. This power override model has an electric coupler that can be plugged into your vehicle towing power to operate the jack in case of loss of power in your trailer. The Magnum gooseneck trailer jack is a heavy duty self-contained system that is shipped with mounting brackets, hardware, electrical cord, control box, less oil. You will need one quart of Dexron III transmission fluid.
The hydraulic valve assemby is designed so it will not leak off.